The quarantine of three South Australian tomato producers has led to hundreds workers being stood down as authorities try to contain a highly contagious plant disease.

Perfection Fresh Australia’s Two Wells operation has been quarantined as well as sites connected to Gawler River Tomatoes and South Australia Tomato.

It understood about 500 workers could be affected by the temporary closures designed to stop the spread of tomato brown rugose fruit virus.

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“It means no tomatoes can be moved off that site, bringing all tomato growing and production to a halt with no indication of when it might resume,” Perfection Fresh said.

“As a result, Perfection Fresh has no choice but to cut jobs in its tomato business.”

Perfection Fresh is scrambling to find roles elsewhere in the industry for its workers until quarantine of its site is over.

Chief executive Michael Simonetta said he hoped to re-hire the employees when production resumed.

He said the company’s fruit and vegetable operations in other parts of Australia are unaffected.

Highly contagious tomato brown rugose fruit virus was detected in South Australia and the Northern Territory in August.

It can lead to deformities in crops and reduced yield of up to 75 per cent, but poses no risk to human health.

The SA government implemented quarantine measures on infected properties.

However, Simonetta said the lockdown of the Two Wells facility was “unnecessary as the virus has been successfully contained”.

“The impact of the lockdown on our employees and their families is simply devastating,” he said.

“With no timeline for when the lockdown might be lifted, we have no choice but to stand down workers — some of whom have been with us for many years.”

Simonetta said Australian growers had discarded tonnes of plants and fruits on instruction from authorities managing the virus, despite the crops not being infected.

Premier Peter Malinauskas said the decision to quarantine the three sites was not taken lightly.

“The objective here is to contain the virus and seek to eradicate it, that may or may not be possible, but where we have a chance to achieve it, we simply must go for it,” he said.

He said most of the workers stood down were seasonal workers from the Pacific Islands and other migrant communities.

“The state government has established a taskforce, one of the actions that is being delivered as a result of that is to establish a workers’ assistance hub,” he said.

“(It) will provide a place where affected workers and employees can go for assistance in English and other languages as well.”

More to come …